<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html>
<html lang="es-419">
<head>
	<meta charset="utf-8" />
<script>
       function validar(){
         var nroi = document.calcula.txtNumInicio.value;
         var nrof= document.calcula.txtNumFin.value; 

         if (nroi == ""){
            alert('Ingrese Numero inicial');
            return false;
         }
  
         if (nrof == ""){
             alert('Ingrese Numero final');
             return false;
          }         
         
         document.calcula.action = "ListarParesServlet";
         return true;
       }
    </script>
	
</head>


<form name="calcula" action="" method="post" onsubmit="validar()" >
	Inicio del rango: <input id="NumInicio" type="text" name="txtNumInicio" maxlenght="5"/>
	Fin del rango: <input id="txtNumFin" type="text" name="txtNumFin" maxlenght="5"/> 
	<input type="submit" />
</form> 

<%
	String msg = (String)request.getAttribute("MENSAJE");
	if ( msg != null ) {
		out.println(msg);
	}
%>
<br>
<a href="bienvenido.jsp">Retornar</a>

</body>
</html>